Adjuvant Hyperthermic Intraperitoneal Chemotherapy in Patients With Locally Advanced Colon Cancer (COLOPEC): 5-Year Results of a Randomized Multicenter Trial
Authors: Emma Sophia Zwanenburg, Charlotte El Klaver, Daniel D. Wisselink, Cornelis J.A. Punt, P. Snaebjornsson, Johannes Crezee, Arend G.J. Aalbers, Alexandra R.M. Brandt-Kerkhof, Andre J.A. Bremers, Pim J.W.A. Burger, Hans F.J. Fabry, Floris T.J. Ferenschild, Sebastiaan Festen, Wilhemina M.U. van Grevenstein, Patrick H.J. Hemmer, Ignace H.J.T. de Hingh, Niels F.M. Kok, M. Kusters, G.D. Musters, Lotte Schoonderwoerd, J.B. Tuynman, Anthony W.H. van de Ven, Henderik L. van Westreenen, M.J. Wiezer, David D.E. Zimmerman, Annette van Zweeden, Marcel G.W. Dijkgraaf, Pieter J. Tanis, Caroline S. Andeweg, Vivian P. Bastiaenen, Willem A. Bemelman, Jarmila D.W. van der Bilt, Johanne Bloemen, Frank C. den Boer, Djamila Boerma, Daan ten Bokkel Huinink, Walter J.A. Brokelman, Huib A. Cense, Esther C.J. Consten, Geert-Jan Creemers, Rogier Crolla, Jan-Willem T. Dekker, Jennifer Demelinne, Marc J. van Det, Karin K. van Diepen, Marjolein Diepeveen, Eino B. van Duyn, Esther D. van den Ende, Pauline Evers, Anna A.W. van Geloven, Erwin van der Harst, Jeroen Heemskerk, Joost T. Heikens, Daniel A. Hess, Bas Inberg, Jan Jansen, Frank W.H. Kloppenberg, Thomas J.M. Kootstra, R.T.J. Kortekaas, Maartje Los, Eva V.E. Madsen, H.C.J. van der Mijle, Linda Mol, Peter A. Neijenhuis, Simon W. Nienhuijs, Loes van den Nieuwenhof, Koen C.M.J. Peeters, Sebastiaan W. Polle, Jolien Pon, Pieter Poortman, Sandra A. Radema, Bert van Ramshorst, Philip R. de Reuver, Koen P. Rovers, Roderick F. Schmitz, Nina Sluiter, Dirkje W. Sommeijer, Eric Sonneveld, T.C. van Sprundel, Sanne C. Veltkamp, Maarten Vermaas, Victor J. Verwaal, Emma Wassenaar, Johannes A. Wegdam, Johannes H.W. de Wilt, Marinke Westerterp, Fennie Wit, Arjen J. Witkamp, Karlijn van Woensdregt, Edwin S. van der Zaag, Mandy Zournas
Journal: Journal of Clinical Oncology (2023)

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. Whether adjuvant hyperthermic intraperitoneal chemotherapy (HIPEC) might prevent peritoneal metastases after curative surgery for high-risk colon cancer is an ongoing debate. This study aimed to determine 5-year oncologic outcomes of the randomized multicenter COLOPEC trial, which included patients with clinical or pathologic T4N0-2M0 or perforated colon cancer and randomly assigned (1:1) to either adjuvant systemic chemotherapy and HIPEC (n = 100) or adjuvant systemic chemotherapy alone (n = 102). HIPEC was performed using a one-time administration of oxaliplatin (460 mg/m 2 , 30 minutes, 42°C, concurrent fluorouracil/leucovorin intravenously), either simultaneously (9%) or within 5-8 weeks (91%) after primary tumor resection. Outcomes were analyzed according to the intention-to-treat principle. Long-term data were available of all 202 patients included in the COLOPEC trial, with a median follow-up of 59 months (IQR, 54.5-64.5). No significant difference was found in 5-year overall survival rate between patients assigned to adjuvant HIPEC followed by systemic chemotherapy or only adjuvant systemic chemotherapy (69.6% v 70.9%, log-rank; P = .692). Five-year peritoneal metastases-free survival rates were 63.9% and 63.2% ( P = .907) and 5-year disease-free survival was 55.7% and 52.3% (log-rank; P = .875), respectively. No differences in quality-of-life outcomes were found. Our findings implicate that adjuvant HIPEC should still be performed in trial setting only.